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zorba
10-24-2012, 09:01 PM
hey everyone trying to build a jib (http://www.sailnet.com/forums/autolink.php?id=28&script=showthread&forumid=4)... dimensions about ..36 luff 34 leech.12.5 foot... been doin a lot of research and that book sailmakers apprentice says you can make rope grommets in stead of using spur grommet or sewn brass rings and a eyelet... i want to know if anyone has seen this technique used on dacron sails or used ever for the luff eyelets which i will attach hanks to.. also rope grommets for head/tack rings? any info would be appreciated.. i have made some and they seem strong but of course will not hold shape as much as a metal ring would... i was thinking.. sewn rope grommets with maybe some 1/2" weebing for xtra support and chafe protection..whatcha think men?? also anyideas for something besides jib hanks? like rope or carabiners or something?

Woxbox
10-24-2012, 09:19 PM
I do believe that's all been done and it works fine. It has most definitely been done with the synthetics designed to look like traditional canvas. But sewing those puppies in is labor intensive and hard on the fingers. My experience after just a handful, anyway.

A new practice for jib hanks is to use synthetic webbing with plastic snap buckles. Not traditional at all, but it's quick and easy and mates well with synthetic headstays. Reports are the plastic stuff is up to the duty.

Todd Bradshaw
10-24-2012, 09:29 PM
I think the biggest problem you'll likely have is that the rope grommets are quite strong, but their round shape will distort badly under a load (distorting the sail's shape in the area immediately around each one). You also don't have much abrasion protection for the stitching, since they won't have the metal liners that both modern hydraulic press rings and traditional sewn rings have. Other options would be to use (1) webbed-on stainless D-rings for the corners (not beautiful, but quite strong and distortion-free) (2) Hand-sewn stainless rings or traditional brass rings with pressed-in brass liners (I think Sailrite still has a couple sizes available) or (3) real rope cringles with brass thimbles stuffed into them (traditional, strong and classy, but a fair bit of work to install). You can anchor them to a linked pattern of sewn-down twine penny grommets or spur grommets. (4) For just the jib snaps, a decent sized spur grommet (probably #2-#3) would work. The #2s are strong enough that I can use them on cat trampolines and walk on them, so they aren't likely to pull out of a jib luff. They would not be strong enough for the corners though. (5) Riveted-on metal plates, or metal plates sewn in between the corner patch layers can also be used for corners.

This is a cringle on the corner.

http://webpages.charter.net/tbradshaw/Sails%20and%20Plans/corner%20detail%201%20copy.jpg

My favorite jib snaps are the Wichard one-handed models. After using them, I'd never go back to piston snaps again.Unfortunately,no jib snap in a large size is cheap.

Vince Brennan
10-24-2012, 09:37 PM
Todd, lovely work, as usual!


Wow.

zorba
10-25-2012, 08:40 PM
hey todd its funny you replied i was really reading deep into using real canvas (cotton) for a sail a ways back, and i remember seeing your picture and reading your posts on the subject (very informative and helpfull by the way.. see the thing is I wanted it to be more repairable on the fly, so trying to steer clear of the metal rings and eyelets cause i gotta buy the tools and the rings... wanted to try make em but the brass ring for the liner was hard to find tubing in that size to attemp to make.. any suggestions there? also couldn't find a way to make the round thimbles and didn't wanna order um for 5 a piece as i live in hawaii... also whatcha think about the rope groms in the corner with webbing to support so it wont distort so much?? and wox thanks for the vote of confidence i am currently leaning towards rope rings and web in the corners with spurs along the luff.. maybe i will go plastic for the snaps, but i dunno i'm weary about them in a strong breeze... hell i'm worried about everything holding up in a strong breeze haha... aloha guys

zorba
10-25-2012, 08:46 PM
hey also i read something along the lines of 1" of hollow per foot of leech..for battenless sail? i personally feel should be deeper to avoid the noise but i have no experiance with hollow battenless leeches boys? i feel your the guys to ask.. Y:o

zorba
10-25-2012, 08:49 PM
ah vince thanks for the heli and the boats.. hoope they find me!! love the old artwork on that site actually stumbled onto it before... hand seaming those long seams in heavy dac is surelly maddening

Todd Bradshaw
10-25-2012, 09:44 PM
Leech hollow is more like 1" per every 10' of leech length and on big sails, sometimes as little as 1.7%-2% of total leech length if the fabric is pretty stable. I don't see any way that you are going to limit corner distortion properly without some sort of fitting that is hard enough to hold its shape. Rope and webbing alone just aren't going to do the job.

At some point, you simply have to realize that decent sails aren't cheap. The fabric isn't cheap, the hardware isn't cheap and some of the tools needed to install that hardware and assemble the sail aren't cheap. I own over $1,000 worth of grommet setters alone. I'm sure that I could have found something far more entertaining to spend that money on, but I need to be able to set grommets and they have to be set properly, so I have no choice. The fact that somebody wants to save money by making their own sails doesn't change these things and one look at an awful lot of the home-built sails where the builder wasn't equipped with the tools or know-how to do the job properly clearly point this out. Trying to build a 40 foot boat on a dinghy budget isn't usually very successful, yet many of the folks trying to do it don't seem to understand that. Nobody is going to build a sail that would qualify as "good" or even "decent" in terms of durability, performance or appearance without spending some fairly serious money on it and without learning a fair bit about designing, cutting and assembling sails. It's just not going to happen.

Bob Cleek
10-26-2012, 02:02 PM
Todd is so right. As much as we'd all like to think we can do just about anything on our boats ourselves, making a new sail from scratch is not just a trade skill, but an art. There isn't any way to make your own sails decently unless you ARE an experienced sailmaker. Maintenance and repairs? Sure. But an new sail in the firstplace, no way. A well-cared for quality sail with today's synthetics should last the life of the boat... or the length of your life, at least. While the first cost may be high, it's quite reasonable over the life of the boat. You can't say the same of much that's for sale in our world today.

zorba
10-26-2012, 09:12 PM
theres no way it'll last that long... unless you aren't Really sailing... and we gotta make work with what we got or are willing to procure eh mate..:ycool:

Todd Bradshaw
10-26-2012, 11:28 PM
By contrast, I suppose I could say that your boat should have sails built with the proper materials, hardware and skills....... unless you aren't really sailing. I applaud anyone willing to try building their own sails, but if you're really sailing, there are going to be some costs that you just have to bear. You're not going to build a good sail with substandard materials and hardware, and the required skills to design and build those sails have to come from somewhere. You can spend the time studying and practicing to learn those skills over a period of years, or you can rent them in the form of pre-cut kits, but they aren't just going to fall out of the sky like magic.

zorba
10-29-2012, 09:35 PM
By contrast, I suppose I could say that your boat should have sails built with the proper materials, hardware and skills....... unless you aren't really sailing. I applaud anyone willing to try building their own sails, but if you're really sailing, there are going to be some costs that you just have to bear. You're not going to build a good sail with substandard materials and hardware, and the required skills to design and build those sails have to come from somewhere. You can spend the time studying and practicing to learn those skills over a period of years, or you can rent them in the form of pre-cut kits, but they aren't just going to fall out of the sky like magic.


well thanks for the applauds and I have been sailing... i know what it does to ones wallet (even when you do the repairs yourself) and time ...also the blood,sweat,tears, and cursing... and I have been studying hard/learning a lot.. didn't really want a lecture on what skills u need or all that just wanted to know the questions i asked..i dont know everything, prob never will but I am improving with time and effort.. I also know ships have sailed the seas long before the "proper materials, hardware" you said I need has existed... so i was curious...i have had to spend money to do all the repairs I have, but with skills effort and much study.. I have also saved tons by not buying expensive things from certain sources when others work just as well...and thanks for the tip I guess i should stop staring at this darn cloud waiting for my grommet tools and hanks to land in this net i set up :rolleyes:

Chip-skiff
10-29-2012, 09:44 PM
It wouldn't cost a lot to make test sails from plastic tarp, with duct tape and spur grommets. If you have local timber that works for mast and spars, you could try different rigs without great financial pain. I've done it and enjoyed the process. But once you decide on your best option and build a "keeper" rig, I think it makes sense to use the best material you can afford, and save up for a quality sail. Bradshaw helped me work out the design for my lug sail and did a beaut job of cutting and sewing. Real craftsmanship is worth a bit extra.

Todd Bradshaw
10-30-2012, 04:36 AM
Actually, the sail hardware on those ships (which is pretty much the same stuff you should be using) has existed for a very long time, as have the skills to use the materials of the day and get the most out of them. The level of actual craftsmanship and skill to assemble sails these days is minimal by comparison. It's been replaced by machine-powered factory work, which can be done by somebody with minimal training who doesn't have to know anything about sails or sailing. As long as you have one person who can feed the proper information into the computer, the rest can be drones and you can produce a pretty decent sail.

I'm still amazed though, that on this reasonably classy boating forum that I have to try to convince so many folks who claim to be good sailors, that their boat should have proper sails that actually work well. If they were all building their boats from AC plywood over red oak frames and slathering them with polyester resin I could understand their acceptance of crappy sails, but some of these boats are very nicely done, with a lot of hours and dollars invested.